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"Owl Monkeys". Nocturnal, 12 species found throughout South America and Panama

Catarrhines

OWMs, all quadrupeds. Compared to NWMs, they are biochemically and physically more similar to humans (same dental formulae 2-1-2-3), inhabit a wider range of environments.

Colobines

OWMs, includes 10 genera and 50 species. Found throughout Africa and Asia. Folivorous (35-75%), with specialized 4-chambered gut that allows digestion of leaves and deactivates toxins. Long tails, diverse coloration. Variation in newborn coat color.

Cercopithecines

Very diverse subfamily, consisting of 12 genera and 71 species. Mostly limited to sub-saharan africa, except Macaques, which are found in other areas. Some live in very large social groups (250 individuals). Good analogies for evolution of early hominids

Gibbons (Is a Lesser Ape, everything else is a Greater Ape in terms of hominoids)

Extremely long arms relative to body and legs. Long fingers, short thumb (stays out of way while swinging), use hands like hooks to swing from branches. No sexual dimorphism in body size. Monogamous, mate for life. Both sexes have large canines.

Gorillas

Characterized by extreme sexual dimorphism. Diet is ~85% leaves, so have special intestinal modifications. Social group uni-male: one male, several adult females and their off-spring

Orangutans

Found only in tropical rain forests in Borneo and Sumatra. Vegetarians, 60% fruit. Not enough food to support large groups. Solitary Social Groups: Mother & Infant. Little danger of predators, so males not needed for protection. Uni-male

Chimpanzees

Two species: Common Chimps and Bonobos. Seperated by Congo River. Central & West Africa. Sexual dimorphism between humans and gorillas. 70% fruit diet. Large Communities of 50 or more. Social structure constantly changes. Terrestrial and Arboreal.

Bonobos

Sex: Often recreational, used to reinforce bonds and resolve conflict, relaxed mating during 20 day estrous period
Dominance: Peaceful, Egalitarian societies, Mother-son bonds, females form bonds for mutual support and protection, killings almost unheard

Taphonomy is the study of decaying organisms over time and how they become fossilized. Taxonomy is the system of classifying organisms.

Mating Systems

Solitary, Polygyny(One-Male), Monogamy, Polygyny(Multimale), Polyandry. In polygynous groups, males compete against other males to control mating access. In monogamous groups only a single male is present(little selection favoring larger males)

Favors: Traits in males that increase the fitness of their mates, indicate good genes and thus increase the fitness of the offspring, and nonadaptive traits that make males more conspicuous to females.

Analogous vs Homologous

analogous=similar in function but not evolutionary origin
homologous=similar in function and in evolutionary origin

Non-divergent big toe is used for pushing off when walking rather than grasping. Spine aids in balance when walking, spinal columns are vertical allowing the weight to be transmitted down through center of body. Curved, aids in shock absorption.

Balance: Pelvis (How we walk upright)

Human pelvis is shorter and wider than apes. Shortness allows greater stability when we stand upright. Certain muscles attach more on the side aiding in balance without the need to bend knees. Butt is also larger, aids in standing and climbing.

Balance: Legs (How we walk upright)

Weight is over our knees. Valgus Angle of Femur

K-Selection

Putting lots of resources towards caring for offspring, means you have less total offspring.

Focuses on overall physical similarities to group organisms. Counts both primitive and derived traits that are
shared, doesn’t distinguish between homologous and convergent/parallel traits. (Lizard and Crocodile Simliar)

Allometry

Study of the relationship of body size to shape, anatomy, physiology and finally behaviour